In recent years, all kinds of detectors manufactured using the MEMS (microelectromechanical systems) technology are widely used in industry, commerce and everyday life, in support of applications of, such as, surveillance and/or control functions. These detectors may be wired or wireless and provide a variety of electrical parameters such as voltage, current, frequency etc., that may be provided to various measurement or application circuits, to be used as equivalent physical, chemical, biological, and other types of measured parameters in generating measurement results or for further applications. These detectors are in small size, consume low power and often provide wireless communication capabilities. Combinations of different sensing parameters thereof are provided for sophisticated monitoring and control functions.
However, although the conventional detectors are smaller in size, most of them can only provide a small number of detecting functions. If a particular monitoring or control function needs to use more sensing parameters, mostly the sensing device designer would need to provide a plurality of detectors that perform different detection capabilities in one large circuit or a PCB. This definitely results in an increased volume of the sensing device, higher power consumption, and higher complexity. Design and manufacturing costs are thus increased.
To further reduce the size of the sensing device and to improve manufacturing efficiency, the industry has proposed the solution of single chip, multi-functional sensing device, wherein detectors of different capabilities are combined and provided in a single substrate.
EP2759802A2 discloses a multi-axis integrated MEMS inertial sensing device on single packaged chip. The MEMS device includes a three-axis accelerometer and a plurality of gyroscope, both integrated on a substrate. The sensing device may be used to provide a variety of sensing functions.
US 20140300490 A1 discloses a wearable electronic device comprising a processor with memory capability. The device is coupled to a body area network (BAN) and can be connected to the WAN. The device has firmware connectable to the WAN to download application programs and settings and to upload data to a server.
WO2014143812 A2 discloses a multi-modal fluid condition sensor platforms and system, used in the measurement of various parameters of a liquid circulation system in various modes simultaneously. The invention is applicable in liquid circulation systems such as a reciprocating engine and automotive vehicle transmission. Embodiments in this patent publication pertain to the following measurement modes: differential temperature comparison, differential magnetic sensor comparison, differential inductive sensor comparison, differential electrical impedance comparison, differential optical absorption comparison,
US2014264657 provides a design that integrates a variety of detectors on a single semiconductor substrate. The invention discloses a monolithically integrated multi-sensor device. In one embodiment, formed on a single substrate is a variety of detectors, including, for example a magnetometer, an infrared detector, an accelerometer and a hygrometer.
U.S. patent application Ser. No. 14/698,392 relates to a dual-functional resonance magnetometer. The magnetometer measures a magnetic field applied to its mass block under a resonant mode and motion or acceleration of the mass block under a non-resonant mode. According to the embodiment, a filter is used to simultaneously produce values of the magnetic field and the acceleration, when working under the resonance mode.
From the above discussion of the prior art, it is appreciated that there is a strong demand in the industry for a device that provides measurement of multiple sensing parameters on one single substrate, particularly a silicon substrate. Developers have been working hard in response to such demand, to provide devices that integrate a variety of sensing features on one circuit board or a semiconductor substrate. However, the sensing devices so developed, which can be called “general-purposed multi-functional detectors,” would be used in a product that includes other supporting hardware and/or software and simply provide particular detecting function or limited number of detecting functions that the general-purposed multi-functional detector is equipped. It is definitely a waste of the powerful general-purposed multi-functional detectors.